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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
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 * file and include the License file at packager/legal/LICENSE.txt.
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 * GPL Classpath Exception:
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 * file that accompanied this code.
 *
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 * If applicable, add the following below the License Header, with the fields
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package org.javaee7.servlet.event.listeners;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * @author Arun Gupta
 */
@WebServlet(urlPatterns = "/TestServlet")
public class TestServlet extends HttpServlet {

    private static final long serialVersionUID = -535776072448287787L;
    
    public static StringBuffer eventBuffer = new StringBuffer();

    /**
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        eventBuffer.setLength(0);
        
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        
        out.println("<!DOCTYPE html>");
        out.println("<html>");
            out.println("<head>");
                out.println("<title>Servlet Event Listeners</title>");
            out.println("</head>");
            out.println("<body>");
                out.println("<h1>Servlet Event Listeners</h1>");
                
                out.println("<h2>Setting, updating, and removing ServletContext Attributes</h2>");
                request.getServletContext().setAttribute("attribute1", "attribute-value1");
                request.getServletContext().setAttribute("attribute1", "attribute-updated-value1");
                request.getServletContext().removeAttribute("attribute1");
                out.println("done");
        
                out.println("<h2>Setting, updating, and removing HttpSession Attributes</h2>");
                request.getSession(true).setAttribute("attribute1", "attribute-value1");
                request.getSession().setAttribute("attribute1", "attribute-updated-value1");
                request.getSession().removeAttribute("attribute1");
                out.println("done");
        
                out.println("<h2>Setting, updating, and removing ServletRequest Attributes</h2>");
                request.setAttribute("attribute1", "attribute-value1");
                request.setAttribute("attribute1", "attribute-updated-value1");
                request.removeAttribute("attribute1");
                out.println("done");
        
                out.println("<h2>Invalidating session</h2>");
                request.getSession().invalidate();
                out.println("done");
        
                out.println("<br><br>Generated output:");
                out.println("<pre>");
                out.println(eventBuffer.toString());
                out.println("</pre>");
            out.println("</body>");
        out.println("</html>");
    }

}
